Sabellariidae - Virginia Institute of Marine Science

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Sabellariidae Sabellaria vulgaris is the only species from Virginia Sabellidae 1a. Worm is very small, with 12 or less setigers. ………………………………………..2 b. Worm with more than 12 setigers.. …………………………………………………..3 2a. Tentacular crown with 2 pair of radioles; pygidium without eyespots; helpful hint : this is a freshwater species.. ……………………………………….Manayunkia speciosa b. Tentacular crown with 3 pairs of radiaole; pygidium with eyespots; helpful hint : this is a species present in saline waters..……………………………………….Fabricia sabella 3a. Collar is 4 lobed; helpful hint: 1-8 large eyes present on radioles in a single row ………………………………………………...…………….Pseudopotamilla reniformis b. Collar is bilobed; helpful hint : eyespots present or absent from radioles……………...4 4a. Radioles without eyes; dorsally, collars come together at their bases, forming a v-shaped gap. …………………………………………………………....Potamilla neglecta b. Radioles with numerous, scattered eyes; dorsally, collars are widely separated, and do not come together forming a v-shaped gap (see below)……...Demonax microphthalmus

Demonax microphthalmus, anterior end

Radioles with eyes Collars are widely separated dorsally

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Scalibregmidae Scalibregma inflatum is the only species from Virginia Serpulidae 1a. Two spoonlike, membranous, transparent opercula present on two stalks dorsal to three pairs of radioles; barbules usually present on the stalks; helpful hint: tubes are small and quite thin, usually intertwining in a lacy, coral like network……..Filograna implexa b. One operculum present, with a spiny, chitinous crown, on a single stalk formed from fused radii, dorsal to about 20 radioles; barbules absent from the stalks………………....2 2a. Operculum with some large spines curving inwards, and some curving outwards from the center (see below).……………………….………………....…….Hydroides dianthus

b. Operculum with all large spines curving outwards (see below).Hydroides protulicola

Siglionidae 1a. Cirriform branchiae absent from notopodia. …………………………..Phloe minuta

Hydroides protulicola, operculum

All large spines curve outwards

Hydroides dianthus, operculum

Some large spines curve inwards

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b. Cirriform branchiae present on all but anteriormost notopodia (see below)…………2

2a. Prostomium without a median antennae, with two small lateral antennae on anterior edge of prostomium; elytra with a fringe of pinnate, branched papillae on the edge (see below); helpful hint : palps are usually quite long, about 4-5 times longer than tentacular cirri……………………………………………………………………..Sigalion arenicola

Sigalion arenicola, middle parapodia, view from posterior

Cirriform branchae present

Siglion arenicola, elytra, ventral view

Pinnate papillae on elytra edge

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b. Prostomium with median antennae, with two small antennal ctenidia at base of median antennae (see below); elytra with a fringe of simple papillae (see below), or without any fringe of papillae; helpful hint : palps are long, but usually only 2-3 times longer than tentacular cirri…...………………………………………………………………………...3

3a. All elytra with an obvious fringe of simple papillae on the external border; elytra opaque, with microtubules. ………………………………………………..Sthenelais boa b. Anterior elytra with a small fringe of simple papillae on external boder, middle and posterior elyta without a fringe of papillae, but with a lateral notch; elytae translucent, without microtubules..……………………………………………….Sthenelais limicola Spionidae 1a. Setiger 5 enlarged relative to nearby setigers, with setae that are much stouter than nearby setigers (see below)...…………….……………………..…………………………2

Sthenelais boa, prostomium

Median antennae, with two ctenidia at base

Sthenelais boa, middle elytra

Elytra with fringe of simple papillae

Polydora cornuta, anterior end, right palp removed

Setiger 5 with stout setae

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b. Setiger 5 not enlarged relative to nearby setigers, with setae that are as stout as nearby setigers…………………………………………………………………………………….7 2a. Branchiae present on setigers 2, 3, 6 and subsequent setigers; notopodia of posterior segments with recurved, hook- like spines; helpful hint : often found in bivalve shells. ………………………………………………………………………....Boccardia hamata b. Branchiae begin on setigers 6-8, and present on subsequent setigers; notopodia of posterior segments without recurved, hook- like spines..………………………………….3 3a. Hooded hooks begin on setigers 10-17; palps fairly short, extending backwards only to setiger 6 at most (see below); caruncle absent; helpful hint : found in shells inhabited by hermit crabs.. ……………………………………………………..Polydora commensalis

b. Hooded hooks begin on setiger 7; palps are long, extending backwards beyond setiger 6; short or long caruncle present.…………………………...……………………………..4 4a. Small nuchal tentacle present (see below); helpful hint : anteriormost portion of prostomium usually T-shaped (see below); builds fragile mucus and mud tubes…………………………………………………………………….Polydora cornuta

Polydora commensalis, anterior end

Short palps

Polydora cornuta, anterior end, right palp removed

Anteriormost portion of prostomium usually T-shaped Small nuchal tentacle present

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b. Small nuchal tentacle absent; helpful hint : anteriormost portion of prostomium usually cleft, but usually does not flare laterally, forming a T-shape; may or may not form mucus and mud tubes…………………….……………………………………………………….5 5a. Modified setae of setiger 5 with pectinate, or bushy tops (see below); pygidium consists of 4 equal lobes; helpful hint : modified setae of setiger 5 are strongly falcate, and the tips are nearly at right angles to the shafts . …………………...…..Polydora caulleryi

b. Modified setae of setiger 5 without pectinate, or bushy tips; pygidium usually cup shaped, with a dorsal gap in it; helpful hint : modified setae of setiger 5 may have slightly curved tips, but they are not strongly falcate..…………………………………………….6 6a. Caruncle terminates at the beginning of setiger 3; anteriormost end of prostomium slightly notched or rounded (see below); branchiae begin on setiger 7 (see below); modified setae of setiger 5 with a lateral flange; helpful hint : bores into calcareous structures, most notably oyster shells.. ……….……………………….Polydora websteri

b. Caruncle terminates at setigers 4-9; anteriormost prostomium deeply cleft and V- shaped; branchiae usually begin on setiger 8 (rarely on setiger 7 or 9); modified setae of setiger 5 without a lateral flange ………………………………………Polydora socialis

Polydora caulleryi, falcate 5th setae with pectinate tops

Polydora websteri, anterior end Branchae begin on 7th setiger

Anteriormost end end of prostomium slightly cleft

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7a. Branchiae entirely absent; neuropodia of setiger 1 includes 1-2 pairs of stout, recurved setae (see below), and capillary setae; helpful hint: capillary notosetae of setiger 1 are usually slightly longer than subsequent notosetae (see below); elongated notopodial lobes are present, beginning on setiger 1 (see below), and these should not be confused with branchiae……………………………………………………………………………..8

b. Branchiae present; neuropodia of setiger 1 without 1-2 pairs of stout, recurved setae. …………………………………………………………………………………………….9 8a. Prostomium triangular, with conspicuous lateral horns (below)...Spiophanes bombyx

Spiophanes bombyx, anterior end

Lateral horns on triangular prostomium

Spiophanes wigleyi, anterior end

Long capillary notosetae of setiger 1 Stout, recurved setae Elongated notopodial lobes, not branchae

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b. Prostomium oval, without conspicuous lateral horns (see below)...Spiophanes wigleyi

9a. One pair of smooth branchiae present on setiger 1; conspicuous dorsal crest, or hood, present across setiger 2. …………………………………………..Streblospio benedicti b. More than one pair of branchiae present; conspicuous dorsal crest, or hood, absent from setiger 2. …………………………………………………………………………...10 10a. Three pairs of pinnate branchiae present, on setigers 1 to 3 (see below); helpful hint : branchiae may be missing, look for scars; prostomium rounded, enclosed laterally by the peristomium in a collar- like fashion; ventral sabre setae present, beginning on setiger 9 …………………………………………………………………...Paraprionospio pinnata

b. More than three pairs of branchiae present, on more setigers. ……………………….11 11a. Branchiae present on 20 or more setigers; branchiae begin on setigers 1 or 2 ….....12 b. Branchiae present on 4 to 12 setigers; branchiae begin on setiger 2 only …………....21 12a. Branchiae begin on setiger 2. ……………………………………………………....13

Spiophanes wigleyi, anterior end

Rounded prostomium

Paraprionospio pinnata, anterior end, side view

3 pairs of pinnate branchae present

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b. Branchiae begin on setiger 1….……………………………………………………….17 13a. Prostomium rounded or slightly bilobed anteriorly; anterior branchiae are completely separate from notopodial lobes……………………………………………...14 b. Prostomium is acutely pointed anteriorly (see below); anterior branchiae are completely or basally fused to notopodial lobes (see below).. ………………………….15

14a. Prostomium without occipital antennae; helpful hint: large pigment patch present on dorsal prostomium in fresh specimens…………………………….Microspio pigmentata b. Prostomium with occipital antennae (see below); helpful hint : large pigment patch absent from dorsal prostomium. …………………...……………………..Laonice cirrata

Laonice cirrata, anterior end

Occipital antennae present

Scolelepis texana, anterior end

Acutely pointed prostomium Anterior branchae fused to notopodial lobes

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15a. Occipital antennae absent; helpful hint : 1st setiger with notosetae present; neuropodial lamellae are notched and bilobed, beginning around setiger 18 (see below)..…….………………………………..……………………….Scolelepis squamata

b. Occipital antennae present..……………………………..…………………………….16 16a. 1st setiger without notosetae present; neuropodial lamellae are cleft, beginning around setiger 28..……………………………………………………….Scolelepis texana b. 1st setiger with notosetae present; neuropodial lamellae remain entire throughout..………………………………………………………….Scolelepis bousfieldi 17a. Posterior notosetae include hooded hooks (see below); branchiae present on anterior 1/2 to 2/3 of body only; prostomium bilobed, and slightly T-shaped anteriorly; helpful hint: this is most common in oligohaline areas. …………………....Marenzelleria viridis

Scolelepis squamata, middle parapodia

Bilobed neuropodial lamellae

Marenzelleria viridis, posterior parapodia

Hooded hooks present

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b. Posterior notosetae without hooded hooks; branchiae present to posterior segments; prostomium pointed or rounded anteriorly.. …………………………………………….18 18a. Prostomium pointed anteriorly; small, accessory branchiae present as digitiform projections posterior to main branchiae, beginning on setigers 18-28; helpful hint : notosetae of setiger 1 are exceptionally long, subequal to, or extending beyond the tip of the prostomium.. ………………………………………………………....Dispio uncinata b. Prostomium rounded anteriorly; small, accessory branchiae absent; helpful hint : notosetae of setiger 1 usually do not extend beyond the tip of the prostomium ………...19 19a. Neurosetal hooded hooks number from 15-20, beginning on about setigers 13-15 .. ………………………………………………………………………………….Spio setosa b. Neurosetal hooded hooks number from 6-10, beginning on about setigers 10-15 …...20 20a. Neuropodial hooded hooks are tridentate..………………………….Spio pettibonae b. Neuropodial hooded hooks are bidentate.. …………………………….Spio filicornis 21a. 4 or 5 pairs of branchiae present; at least one pair of branchiae are pinnate ……..22 b. More than 5 pairs of branchiae present; all branchiae are apinnate………………….27 22a. 5 pairs of branchiae present, branchiae on setigers 2, 5 and 6 are pinnate; helpful hint: two pairs of eyes present in fresh specimens, with posterior pair quite large, larger than anterior pair..………………………………………….Prionospio heterobranchia b. 4 pairs of branchiae present, pinnate branchiae otherwise; helpful hint: in fresh specimens, eyes, if present, with posterior pair small, usually subequal to anterior pair.. ………………………………………………………………………………………….23 23a. Branchiae on setigers 2 to 4 apinnate, branchiae on setiger 5 pinnate, and longer than the other branchiae; pinnules on pinnate branchiae are plate- like, not digitiform……...24 b. Branchiae on setigers 3 and 4 apinnate, branchiae on setigers 2 and 5 pinnate; pinnules on pinnate branchiae are digitiform, not plate- like. …………………………………….25 24a. Notopodial lamellae are connected in a large dorsal crest on setiger 7 (see below) ……………………………………………………………………….Apoprionospio dayi

Apoprionospio dayi, anterior end

Dorsal crest on setiger 7

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b. Notopodial lamellae are not connected in a dorsal crest on setiger 7 .……………………………...…………………………………..Apoprionospio pygmaea 25a. Prostomium distinctly shovel shaped anteriorly, as it is broadest anteriorly, and with a straight edge (see below); helpful hint: pairs of pinnate branchiae are subequal in length (see below). ……………………………………………………….Prionospio steenstrupi

b. Prostomium otherwise, slightly narrower anteriorly than in mid-region, and rounded anteriorly; helpful hint : pinnate pairs of branchiae either subequal in length, or anteriormost pair are longer than posterior pair. ………………………………………..26 26a. Anteriormost pair of pinnate branchiae are larger than posterior pair; dorsal crests absent from setigers 7 and 9; without a pair of prominent nuchal organs fused over caruncle..……………….……………………………………………….Prionospio dubia b. Pinnate pair of branchiae are subequal in length; notopodial lamellae form dorsal crests across setigers 7 and 9; with a pair of prominent nuchal organs fused over the caruncle..…………………………………………………..………….Prionospio cristata 27a. Inward curving ventral sabre setae present, beginning on setiger 10; 6-8 pairs of branchiae present; helpful hint : hooded hooks are multidentate……..Prionospio cirrifera

Prionospio steenstrupi, anterior end, side view

Shovel shaped prostomium

Pinnate branchae sub-equal

Prionospio cirrifera, ventral sabre setae

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b. Ventral sabre setae absent; 6-12 pairs of branchiae present; helpful hint : hooded hooks are either multi dentate, or bidentate……………………………………………………28 28a. Anteriormost 3 pairs of branchiae are obviously longer than subsequent branchiae; 6-10 pairs of branchiae present; hooded hooks are multidentate …...Prionospio perkensi b. All branchiae are subequal; 10-12 pairs of branchiae present; hooded hooks are bidentate..………………………………………………….Prionospio cirrobranchiata Syllidae 1a. Ventral cirri absent; pharyx coiled or sinuous; helpful hints: palps are completely fused; nuchal organs present as small or large epaulettes..……………………………….2 b. Ventral cirri present; pharyx usually straight; helpful hints: palps completely fused, or otherwise; nuchal organs usually not as epaulettes..………………………..…………….6 2a. Dorsal cirri short, shorter than width of body (except first two pairs); dorsal cirri without cirrophores (see below)………………………………………………..………….3

b. Some dorsal cirri long, equal to, or longer than, the width of the body; dorsal cirri with cirrophores..……………………………………………………………………………….4 3a. Body with transverse bands; nuchal epaulettes conspicuous, extending to posterior portion of setiger 1...…………………………………………………Proceraea fasciata b. Body with lateral longitudinal bands; nuchal epaulettes inconspicuous, extending only to the tentacular segment..…………………………………………….Proceraea cornuta

Proceraea cornuta, anterior end

Short dorsal cirri, without cirrophores

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4a. Dorsal cirri on setiger 2 are subequal to dorsal tentacular cirri and lateral antennae, obviously longer than subsequent dorsal cirri (see below); helpful hint : conspicuous nuchal epaulettes present, extending to setigers 2 to 4 (see below)….Autolytus alexandri

b. Dorsal cirri on setiger 2 are shorter than dorsal tentacular cirri, and lateral antennae, only slightly longer than subsequent dorsal cirri; helpful hint : nuchal epaulettes may or may not be prominent..………………………………..………………………………….5 5a. Nuchal epaulettes prominent, extending to setigers 3-4; trepan with about 30 teeth. ……………………………………………………….……………….Autolytus dentalius b. Nuchal epaulettes not prominent, not extending beyond setiger1; trepan with 10 teeth. ……………………………………………………………………….....Autolytus prolifer 6a. Two pairs of tentacular cirri present; helpful hint : dorsal cirri subequal to, or greatly exceeding the length of the parapodia; tentacles and/or dorsal cirri may or may not be clearly articulated; worm may or may not be large, exceeding 10 mm in length……….13 b. One pair of tentacular cirri present; helpful hint : dorsal cirri subequal to, or shorter than parapodia, never greatly exeeding the length of the parapodia; dorsal cirri and tentacles never clearly articulated; worm is always less than 10 mm in length………....7 7a. Body with a covering of adhesive papillae, usually encrusted with mud; helpful hints: dorsal cirri absent from setiger 2, and replaced by a small papillae; palps almost completely fused; tentacular cirri are well developed, and are similar to the dorsal cirri...8 b. Body smooth, without adhesive papillae; helpful hints: dorsal cirri present or not on setiger 2; palps completely or only partially fused; tentacular cirri well developed, or not..……………………………………………………………………………………….9

Autolytus alexandri, anterior end

Dorsal cirri of setiger 2 obviously longer than subsequent dorsal cirri Conspicuous nuchal epaulettes present

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8a. 4 eyes present; spherical parapodial glands, containing needle- like rods present, beginning on setiger 4...……………………………………………Sphaerosyllis taylori b. 6 eyes present; spherical parapodial glands completely absent ……..…………………………………………………………...Sphaerosyllis longicauda 9a. Palps fused on basal third only (see below); tentacular cirri well developed (see below); helpful hint : dorsal cirri present on setiger 2..……...Parapionosyllis longicirrata

b. Palps completely fused (see below); tentacular cirri rudimentary (see below); helpful hint: dorsal cirri present or not on setiger 2..…………………………………………….10

10a. All 3 prostomial antennae are minute and subequal, much shorter than the length of the prostomium.………………………………………………………..Exogone verugera b. At least one prostomial antennae is long, exceeding the length of the prostomium...11

Parapionosyllis longicirrata, anterior end

Palps fused at base only Tentacular cirri well developed

Exogone verugera, anterior end

Palps completely fused Tentacular cirri rudimentary

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11a. All 3 antennae on the prostomium are subequal in length (see below); helpful hint : dorsal cirri absent from setiger 2..……………………………………….Exogone naidina

b. Median antennae is longer than two lateral antennae; helpful hint : dorsal cirri present or not on setiger 2……………….……………………………………………………….12 12a. Dorsal cirri present on setiger 2 anterior parapodia with three types of setae: simple curved upper one, compound spinigers, and compound falcigers ……….Exogone dispar b. Dorsal cirri absent from setiger 2; anterior parapodia with all setae as compound falcigers..………………………….……………………………………….Exogone hebes 13a. Most dorsal cirri are clearly articulated, resembling a string of beads; helpful hint : antennae and tentacular cirri may or may not be articulated as well…………………….14 b. Most dorsal cirri are smooth, or with indistinct articulation; helpful hint: antennae and tentacular cirri never are articulated.……………………………..……………………..19 14a. Antennae, tentacular cirri, and first two pairs of dorsal cirri are not distinctly articulated; worm is small, less than 5 mm in length…………………………………...15 b. Antennae, tentacular cirri and first two pairs of dorsal cirri are distinctly articulated; worm is usually large, 10 mm or more in length……………………………………….16 15a. Palps are short and scarcely visible dorsally; upper simple setae with bifurcated tips..………………………………………………………………….Streptosyllis verrilli b. Palps are large and clearly visible dorsally; upper simple setae with rounded tips..…………………………………………………….………………….Syllides fulvus 16a. All setae are simple..……………………………..………….Haplosyllis spongicola b. Some setae are compound. …………………….……………………………………..17

Exogone naidina, anterior end

Subequal antennae No dorsal cirri on setiger 2

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17a. Setae as follows: anterior setae entirely composite falcigers, replaced by thick simple setae beginning on setigers 14-21, posterior as composite falcigers and slender simple setae..………………………….…………………………………….Syllis gracilis b. Setae otherwise, specifically: all parapodia have compound setae, and simple setae present posteriorly only..…………………………….………………………………….18 18a. Some compound setae with elongated, spinigerous blades (below).…Syllis cornuta

b. All compound setae with shorter, falcigerous blades (below)……………Syllis hyaline

19a. Antennae subequal to, or slightly exceeding the length of the palps, and dorsal cirri on setiger 1 subequal to, or slightly exceeding the length of the setae on setiger 1……..20 b. Antennae greatly exceeding the length of the palps, and/or the dorsal cirri on setiger 1 greatly exceeding the length of the setae on setiger 1…………………………………...22 20a. Dorsal cirri absent from setiger 2; helpful hint : fresh specimens without distinct eyespots…….……………………………………………………….Brania wellfleetensis b. Dorsal cirri present on setiger 2; helpful hint : fresh specimens with distinct eyespots. ………………………………………………………………………………………….21 21a. Dorsal cirri abruptly truncate at tips; compound falcigers with unidentate blades; helpful hint : prostomium with only 4 eyes..……………………………….Brania pusilla b. Dorsal cirri taper to a tip (see below); compound falcigers with minutely bidentate blades; helpful hint : prostomium with 4 eyes, and 2 small eyespots near the bases of the lateral antennae..…………………………………………………………...Brania clavata

Syllis cornuta, compound spiniger

Syllis hyaline, compound falciger

Brania clavata, middle parapodia

Dorsal cirri taper to a tip

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22a. Setigers 2 to 5 with enlarged acicula, with knobbed tips; helpful hint: some dorsal cirri may appear to be articulated..……………………………………………………….23 b. Acicula in setigers 2 to 5 otherwise; helpful hint : all dorsal cirri are smooth, or slightly wrinkled..…………………………………………………..…………………………….24 23a. Compound setal blades with distictive circular hoods at tips; upper simple setae with circular, or semi-circular hood on tips (see below)……………….….Streptosyllis arenae

b. Compound setal blades with bifid tips after setiger 5 or 6; upper simple setae with hood that is excavate at the tips………………………………….Streptosyllis pettibonae 24a. Tentacles on prostomium are short, slightly longer than the lengths of the palps (see below); tentacular segment with a hood that covers the posterior portion of the prostomium (see below)..…………………………………………Odontosyllis fulgurans

b. Tentacles on prostomium are long, greatly exceeding the length of the palps; tentacular segment without hood.……………………………………………….Eusyllis lamelligera Terebellidae 1a. Branched branchiae present on anteriormost segments ………………………………2 b. Branchiae absent from anteriormost segments; helpful hint branchiae- like notopodia may be present in middle region, beginning on about segment 9……………………….8

Streptosyllis arenae Compound seatae Upper simple seatae

Odontosyllis fulgurans, anterior end

Tentacles slightly longer than palps Hood covers posterior portion of prostomium

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2a. Only one pair of branched branchiae present on second segment (see below); helpful hint: numerous small eyespots present on first segment, in fresh specimens ……………………………………………………………………………..Pista maculata

b. Two to three pairs of branched branchiae present on more segments; helpful hint : small eyespots present or absent in fresh specimens……………………………………...3 3a. Two pairs of branchiae present on segments 2 and 3..……………………………….4 b. Three pairs of branchiae present on segments 2, 3 and 4..…………………………….6 4a. Branchiae spirally branched, resembling oval pom-poms on long stalks (see below) ..………………………………………………………………………..…….Pista cristata

b. Branchiae are arborescent, not resembling pom-poms………………………………..5

Pista maculata, anterior end

Only one pair of branchae present

Pista cristata, anterior end

Branchae resemble pom-poms on stalks

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5a. Lateral lobes originating from segment 3 form small, digitiform lobes dorsally, directly posterior to branchiae (see below); first row of uncini without long necks; numerous eyespots absent from segment one in fresh specimens; helpful hint : segment two with large ventrolateral lobes (see below)..………………...…………..Pista palmata

b. Lateral lobes from segment 3 not forming digitiform lobes dorsally; first row of uncini with long necks; numerous eyespots present on segment one in fresh specimens; helpful hint: segment 2 with small, or no ventrolateral lobes………………...Pista quadrilobata 6a. Notopodia present on 17 segments only……………………………………………...7 b. Notopodia present on 40 to 50 segments…………………………..Amphitrite ornata 7a. Uncini with 4 to 6 teeth; helpful hint : buchal segment with large lateral lobes (see below)..…………………………………………………………..………..Loimia medusa

b. Uncini with 6 to 8 teeth; helpful hint : buchal segment with small lateral lobes. ……………………………………………………………………………..Loimia viridis 8a. Branched, branchiae- like notopodia present in middle region, starting at about segment 9..………………………………………………….Enoplobranchus sanguineus

Pista palmata, anterior end

Large ventrolateral lobes on segment 2 Dorsal digitiform lobes from segment

Loimia medusa, anterior end

Large lateral lobes on buchal segment

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b. Notopodia in middle region not branchiae- like. ……………………………………....9 9a. Uncini completely absent; notosetae very fine, and not immediately obvious………………………………………………………………………...Lysilla alba b. Uncini present; notosetae readily apparent; helpful hint : uncini may be inconspicuous. …………………………………………………………………………………..………..10 10a. Thorax with 16 or more notosetae; uncini begin on setiger 7 to 9 ..……………………………………………………………………….Polycirrus eximius b. Thorax with 11 to 13 notosetae; uncini begin on setiger 15 to 16 ....Polycirrus medusa Trichobranchidae Terebellides stroemi is the only species from Virginia